If you own a laptop, desktop computer, or other internet-connected device, you need to know about computer viruses. These malicious programs have been plaguing computer users for decades and continue to pose a significant threat.
In this comprehensive guide, we’ll cover everything you need to know to protect yourself from computer virus infections in 2023 and beyond.
What Exactly Is a Computer Virus?
A computer virus is a type of malicious code or software program specifically designed to damage, disrupt, steal from, or gain unauthorized access to a computer system. Viruses have some similarities to biological viruses in how they self-replicate and spread.
Once they infiltrate a system, computer viruses can deliver an actively harmful payload. Some of the most common effects include:
- Corrupting or deleting important system files
- Infecting other files and programs on your computer
- Stealing personal or financial data such as credit card details
- Using your computer’s resources to mine cryptocurrency
- Clogging up system memory leading to crashes
- Allowing hackers to remotely take control of your device
Left unchecked, viruses can inflict severe damage and be difficult to eliminate.
According to AV-TEST institute, over 850 million new malware samples were registered in 2021, showing viruses and malware remain highly prevalent.
Malware samples detected annually by AV-TEST Institute
A Brief History of Computer Viruses
Computer viruses have been around for a surprisingly long time. Here are some key moments in the evolution of the computer virus:
- 1949 – The concept of a "self-reproducing automaton" is theorized, laying the groundwork for computer viruses.
- 1971 – Creeper virus becomes the first computer virus ever created. It infects DEC PDP-10 computers rather harmlessly.
- 1981 – Elk Cloner virus infects early Apple II systems by copying itself to floppy disks. Considered the first virus aimed at personal computers.
- 1983 – The Term "virus" is first used to describe self-replicating computer programs by Fred Cohen.
- 1986 – The Brain virus is one of the first to target Microsoft Windows, infecting boot sectors of storage media. Still spreads today.
- 1992 – The Michelangelo virus causes widespread disruption by FORMATing hard drives on March 6th.
- 1999 – The Melissa virus infected over 50,000 computers in hours by emailing itself using infected Microsoft Word documents.
- 2000s – Massive new virus outbreaks including ILOVEYOU, Anna Kournikova, MyDoom cause global damage. Countermeasures are developed.
- 2010s – Stuxnet demonstrates viruses being developed for targeted cyberwarfare, attacking Iranian nuclear facilities.
- Present – Polymorphic viruses that rapidly mutate to avoid detection become dominant. Viruses continue evolving.
This abbreviated history shows how computer viruses rapidly evolved from academic experiments into highly damaging cyberattacks once personal computing took off.
How Do Viruses Infect Computers and Spread?
Viruses use a variety of clever infection methods and delivery mechanisms to spread. Some of the most common include:
- Email attachments – One of the most common delivery methods is sending emails with an infected file. Once the attachment is opened, the virus rapidly infects the system.
- Infected downloads – Viruses are often bundled with downloads like free games, video files, pirated software, camouflaged browser extensions, and more.
- Removable drives – USB drives, external hard drives, etc. make easy carriers for viruses between systems. Just plugging one in can trigger infection.
- Network sharing – Viruses spread rapidly across networks by copying themselves onto shared folders and resources.
- Software vulnerabilities – Unpatched weaknesses in operating systems and programs enable some viruses to slip through without any action by the user.
With so many attack vectors, viruses can infiltrate systems in countless ways. Once on a system, their self-replicating nature enables them to spread extensively.
Major Types of Computer Viruses
There are various categories and classifications of computer viruses depending on factors like their delivery method, target, reproductive technique, and payload. Common types include:
|Macro viruses||Infect files like Office documents/PDFs with malicious macros that run when opened.|
|System/Boot Record Viruses||Infect the boot sector of drives/media and activate on system startup.|
|File Infector Viruses||Inject malicious code into program files and executables on a computer.|
|Multipartite Viruses||Utilize multiple techniques like infecting boot record + files for spreading.|
|Stealth Viruses||Hide themselves to avoid detection by antivirus software.|
|Polymorphic Viruses||Constantly change their code to evade antivirus detection.|
With literally millions of viruses and variants in the wild, this list barely scratches the surface. Identifying unique strains is a constant effort for antivirus vendors.
"We discover over 300,000 new virus variants a day. There is no one-size-fits-all solution to stop them. Constant vigilance is required." – Vessal Cheraghmakani, malware researcher at G DATA
Modern Viruses: Should You Still Be Concerned?
Since the early days of computing, computer viruses have continued to thrive and impact systems globally. But with modern operating systems like Windows 10 and Mac OS being much more secure, do typical users still need to worry about virus threats?
The answer from experts is a resounding yes. Here‘s why viruses remain a clear and present danger:
- Sophisticated new viruses are constantly developed, often specifically designed to evade modern defenses.
- Antivirus/anti-malware tools are helpful but not flawless. According to Verizon‘s 2021 DBIR report, antivirus catches less than 70% of attacks.
- Many users still engage in risky cyber behaviors like opening attachments from unknown senders.
- Once unleashed, viruses spread at immense speed across networks and email. New propagation techniques emerge regularly.
- Migrating offline data online creates new virus vulnerabilities.drive-by downloads, media files, infected ads, HTML emails, etc. enable infection through previously safe channels.
- Complacency is rampant. Many users wrongly believe their modern device or OS to be invulnerable.
Industry professionals largely agree – viruses continue to pose a clear threat. Users cannot afford to become apathetic.
"With the exponential spread of viruses via networks and email, a single undetected virus on one system can lead to a massive, coordinated attack affecting millions of systems in hours." – Chester Wisniewski, principal research scientist at Sophos
"Education is key. Too many people engage in behaviors that put them at severe risk online by letting their guard down. Enhanced OS and browser security helps, but unsafe computing practices persist, necessitating constant user vigilance." – Jessica Barker, CEO at Redacted Firm
10 Important Tips to Avoid Viruses in 2023
Staying secure requires proactive effort by the user. Here are 10 vital expert tips to keep viruses off your devices:
- Install antivirus software on all devices – Run ongoing scans and keep virus definitions updated.
- Never open unsolicited email attachments – Even from known contacts. Call to verify if concerned.
- Avoid downloads from unofficial sites – Stick to trusted sources like app stores for software.
- Use VPNs for public Wi-Fi – Encrypt connections to block snooping and drive-by downloads.
- Don‘t use unfamiliar drives or devices – They may carry infected files.
- Disable unnecessary macros – Word/Excel macros are common virus carriers.
- Keep OS, software, & browsers fully updated – Patching stops many infection routes.
- Use ad and script blockers – Reduce exposure to infected ads & sites.
- Backup regularly – Facilitates recovery if infected.
- Don‘t use admin accounts for everyday use – Limit account permissions viruses can exploit.
"The most vital step is using modern antivirus suites like Norton, McAfee, or Avast combined with safe browsing and computing habits. Avoid complacency and proactively safeguard devices." – Ryan Barnett, senior security researcher at Digital Defense Inc.
What To Do if You Get Infected With a Virus
Viruses can slip through even when you take precautions. If you suspect infection, take these steps to isolate and remove the threat:
- Disconnect from Wi-Fi/internet – Contain the threat by preventing communication.
- Boot into Safe Mode – Use Safe Mode to disable any virus processes.
- Run a full system antivirus scan – Quarantine or delete any infections found.
- Check unfamiliar running processes – End Task any suspicious executable files.
- Uninstall/delete recent programs – Newly installed apps commonly carry viruses.
- Disconnect infected drives – Remove any connected infected USB drives or external devices.
- Reset web browsers – Clear browser cookies, cache, extensions, and defaults.
- Change account passwords – Viruses commonly steal credentials and info.
- Repair the registry – Fix corrupted entries that may remain using reputable tools.
- Revert to a clean system image – If the infection persists, restore to an earlier uninfected state.
With dedication and antivirus tools, most viral infections can be defeated. But prevention remains much easier than the cure.
The Cost of Viruses Remains High
Although not all viruses are destructive, the damages from the most insidious variants are immense for individuals and businesses. Some estimated global costs of viruses include:
- The ILOVEYOU virus caused over $15 billion in damages back in 2000.
- The WannaCry ransomware virus caused at least $4 billion in global losses. Victims included corporations, hospitals, and government systems.
- In 2012, normal operations at Aramco, Saudi Arabia‘s national oil company, were disrupted by viruses for over two weeks, impacting business productivity and resources extensively.
- The infamous Slammer worm infected over 75,000 servers in 10 minutes thanks to a rapid spreading mechanism. It caused network outages and connectivity issues worldwide.
- A 2018 SamSam ransomware attack halted medical services at the Hancock Health Hospital in Indiana for days, and cost nearly $55,000 in bitcoin ransom alone.
- The NotPetya virus did over $10 billion in economic damage globally by exploiting supply chain weaknesses after compromising Ukrainian tax software. Maersk and FedEx were among the major victims.
From lost business to repairs, viruses continue inflicting heavy damage to this day.
The Future of Viruses
Looking ahead, experts predict viruses will continue evolving in response to enhanced OS and network security measures:
- More focus on exploiting software supply chain vulnerabilities through infected downloads and tools.
- Utilizing advanced evasion techniques like polymorphism and obfuscation to slip past modern antivirus engines.
- Shift from "spray and pray" random targeting to more concentrated, focused attacks on specific organizations, systems, and valuable data.
- Leveraging cloud services and mobile endpoints with lax security as new attack vectors.
- Ransomware and cryptomining payloads will continue to be lucrative options for virus operators.
In essence, we can expect viruses to become more sophisticated, targeted, and costly. Without proper vigilance, the damage may be unprecedented.
"The cat and mouse game between attackers and security professionals will continue. Just as we adapt, hackers escalate their techniques. By implementing layered defenses across endpoints, networks, email, and users, we create a far more formidable defense." – Maxim Zavodchik, Information Security Officer at InfoSec Institute
The Bottom Line
Computer viruses have been a menace since the early days of computing, but remain highly relevant in 2023. Though device and software security has improved, viruses can still cause extensive damage when given an opening.
With millions of new and evolving threats appearing annually, practicing basic cyber hygiene remains critical. Installing modern antivirus suites, avoiding suspicious downloads and emails, keeping software updated, and backing up regularly are essential precautions.
No single solution can block every virus, but using a defense-in-depth approach goes a long way. Don‘t buy into the myth that viruses are a thing of the past – staying vigilant about these persistent threats is a must!